Unless it was the yard I am landscaping this week (someone should be fined for soil damage like this - worst yet in 15 years) I have not seen roots here that big at drip line.
Most here - a Pin - like 30 year old, are about 50 feet tall, and about 55 feet wide. 30 years here just doesn't produce much root diameter at the drip line area.
Its hard in our area to stick to the letter of the law about trees and roots, because trees grow so fast here. If Portland residents followed the letter of the law, the trees here would run 90% of the gardens, shrubs and lawns out of the area.
Too make it worse, homeowners and even landscape designers really overplant - a huge problem for an area where trees grow so fast, you don't want to tie your horse to a tree.
When I left the golf courses and university campuses to start in business, I almost "blew beets" after about a week of pruning residentially.
It took about 1 month to figure out how to change pruning strategy.
About the only tree that really gets big roots close to the dripline, here, seems to be the Dawn Redwood.